memory-and-storage digital-electronics question and answers -Page 8

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2. The RAM circuit given below is suspected of being bad. A check with a logic probe shows pulse activity on all of the address lines and data inputs. The / line and inputs are forced HIGH and the data output lines are checked with the logic probe. Q0, Q2, and Q3 show a dim indication on the logic probe; Q1 indicates a HIGH level on the logic probe. What, if anything, is wrong with the circuit?
Options
A. The Q0, Q2, and Q3 output lines are open; the chip is defective.
B. The Q1 line appears to be shorted to V_cc; replace the chip.
C. The outputs should be active only when the / line is held LOW, so the circuit is behaving normally considering the fact that the line is HIGH.
D. The EN input should be forced HIGH and the outputs rechecked; if they are still giving the same indications as before, then the three outputs are definitely open and the IC will have to be replaced.